Apache SpamAssassin vs Rspamd
Apache SpamAssassin
spamassassin.apache.orgRspamd
rspamd.comSide by side
| Figure | Apache SpamAssassin | Rspamd |
|---|---|---|
| Price from | Free | £100/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | Yes | Yes |
| Web | — | Yes |
| Windows | Yes | — |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 2 | 5 |
| Spec score · Email Anti-Spam Software | 9.1 (#1) | 8.9 (#3) |
| Spec score · Anti-spam Software | 9.1 (#1) | 9.0 (#2) |
| Deployment | The project wiki says SpamAssassin runs on a server and filters spam before it reaches the mailbox. | The project describes the engine as runnable on-premises, with message data staying in the user's environment and no mandatory vendor cloud dependency. |
| Documentation depth | Documentation includes README, INSTALL, UPGRADE, spamd and SQL-preference guides, wiki material and versioned POD manuals. | Documentation includes installation, configuration, modules, workers, tutorials, developer architecture and protocol material, a Lua API reference and FAQ. |
| License | Apache SpamAssassin is free open-source software under the Apache License 2.0. | The project is licensed under Apache License 2.0, allowing commercial use, modification and redistribution with no warranty. |
| Purpose | SpamAssassin classifies email and helps system administrators block unsolicited bulk email. | Rspamd is an email security engine designed to stop phishing, business email compromise, malicious attachments, and spam. |
| Self-hosting | The product is downloaded as source archives and operated by system administrators on their own mail infrastructure. | Rspamd is designed to run on the operator's infrastructure and can be deployed with packages, Docker or Kubernetes-oriented setups. |
| What it does | Apache SpamAssassin is an open-source filter that classifies email and blocks unsolicited bulk mail. | Rspamd is a high-performance daemon that analyzes email beside a mail-transfer agent and returns a spam score and recommended action. |
Plans
Rspamd
- Open-source RspamdFree
- Scale£100 a month
- Scale£100 a month
- EnterprisePriced on request
- HostedPriced on request
In their own words
Apache SpamAssassin
Apache SpamAssassin is free, open-source software that classifies email to help system administrators block unsolicited bulk messages. It runs on a server to filter mail before it reaches a mailbox. Detection combines header and text analysis, Bayesian filtering, DNS blocklists, collaborative filtering databases, and local and network tests. Its scoring framework and plugins add heuristic and statistical checks. Tests and configuration are stored as plain text, so administrators can adjust settings and add rules. The Mail::SpamAssassin API can be integrated with systems such as procmail, sendmail, Postfix, and qmail. The core distribution includes command-line filtering tools and Perl modules for use in other products. The downloads page lists version 4.0.2 as the released version. Official releases are signed, with GPG signatures and SHA-256 and SHA-512 checksum links for downloads. Users can ask questions on the mailing list; developers and PMC members answer as time permits.
Rspamd
Rspamd is an email security engine for filtering phishing, business email compromise, malicious attachments, and spam. It scores messages using reputation, sender authentication, content analysis, and machine learning. Authentication checks cover SPF, DKIM, DMARC, and ARC; malware scanning can use ClamAV or commercial antivirus engines. Administrators can define custom rules through the Lua API and configurable maps and selectors. Rspamd works with mail transfer agents including Postfix, Exim, and Sendmail, and its ClickHouse and Elasticsearch integrations provide visibility into attack patterns and detection rates. It is designed for gateway deployment and can run on-premises, keeping message data in the operator's environment without a mandatory vendor cloud. The detection engine is open source under Apache 2.0 and is available for Linux, macOS, and self-hosted use. Rspamd says its event-driven C core scans hundreds of messages per second per core and can scale from a single server to billions of messages a day. The open-source engine is listed at free. Scale costs £100 a month, with 5K mailboxes; hosted and enterprise plans have custom pricing. Premium plans offer support from core engineers, with enterprise SLA options.